1.2 Convection Currents and the Mantle

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Vocabulary:

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Heat transfer-movement of energy from a warmer object to a cooler object
Three types:

• Radiation-energy transfer through empty space
• Convection-heat transfer by movement of a heated fluid
• Conduction-heat transfer by movement of a heated fluid

Density-how much mass in a volume of a substance
Convection currents-flow which transfers heat within a fluid

Outline:

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Summary

• heat is always transferred from a warmer substance to a cooler substance.

Radiation

• heat transfer by radiation takes place with no direct contact between the heat source and the object

Conduction

• the heated particles of a substance transfer heat to other particles through direct contact

Convection

• during convection,heated particles of fluid being to flow,transferring heat energy from one part of the fluid to another

Convection in Earth's Mantle

• Earth's mantle responds to heat
• Convection Currents in Asthenosphere
  • convection currents have been moving for more than four billion years
  • at the top of the asthenosphere,hot material spreads out and pushes the cooler material out of the way,then the cooler material sinks back into the asthenosphere